<template>
  <div>
    <!-- 面包屑导航区域-->
    <el-breadcrumb separator-class="el-icon-arrow-right">
      <el-breadcrumb-item :to="{ path: '/home' }">首页</el-breadcrumb-item>
      <el-breadcrumb-item>商品管理</el-breadcrumb-item>
      <el-breadcrumb-item>添加商品</el-breadcrumb-item>
    </el-breadcrumb>
    <!-- 卡片视图区域-->
    <el-card>
      <!-- 警告区域-->
      <el-alert
          title="添加商品信息"
          type="info" :closable="false" show-icon center>
      </el-alert>
      <!-- 步骤条区域-->
      <el-steps :active="activeIndex-0" finish-status="success" align-center>
        <el-step title="基本信息"></el-step>
        <el-step title="商品参数"></el-step>
        <el-step title="商品属性"></el-step>
        <el-step title="商品图片"></el-step>
        <el-step title="商品内容"></el-step>
        <el-step title="完成"></el-step>
      </el-steps>
      <!-- Form表单：不能用el-tabs去嵌套el-form，反过来可以-->
      <el-form :model="addForm" :rules="addFormRules" ref="addFormRef" label-width="100px" label-position="top">
        <!-- 左侧tab栏区域-->
        <el-tabs @tab-click="tabClicked" :before-leave="beforeTabLeave" v-model="activeIndex" tab-position="left">
          <el-tab-pane label="基本信息" name="0">
            <el-form-item label="商品名称" prop="goods_name">
              <el-input v-model="addForm.goods_name"></el-input>
            </el-form-item>
            <el-form-item label="商品价格" prop="goods_price">
              <el-input v-model="addForm.goods_price" type="number"></el-input>
            </el-form-item>
            <el-form-item label="商品重量" prop="goods_weight">
              <el-input v-model="addForm.goods_weight"></el-input>
            </el-form-item>
            <el-form-item label="商品数量" prop="goods_number">
              <el-input v-model="addForm.goods_number" type="number"></el-input>
            </el-form-item>
            <el-form-item label="商品分类" prop="goods_cat">
              <el-cascader
                  v-model="addForm.goods_cat"
                  :options="catelist"
                  :props="cateProps"
                  @change="handleChange"></el-cascader>
            </el-form-item>
          </el-tab-pane>
          <el-tab-pane label="商品参数" name="1">
            <!-- 渲染表单的item项-->
            <el-form-item :label="item.attr_name" v-for="item in manyTableData" :key="item.attr_id">
              <!-- 复选框组-->
              <el-checkbox-group v-model="item.attr_vals">
                <el-checkbox v-for="(cb,i) in item.attr_vals" :key="i" :label="cb" border></el-checkbox>
              </el-checkbox-group>
            </el-form-item>
          </el-tab-pane>
          <el-tab-pane label="商品属性" name="2">
            <el-form-item :label="item.attr_name" v-for="item in onlyTableData" :key="item.attr_id">
              <el-input v-model="item.attr_vals"></el-input>
            </el-form-item>
          </el-tab-pane>
          <el-tab-pane label="商品图片" name="3">
            <!-- action表示图片要上传到的后台API地址-->
            <!-- on-success钩子：只要上传成功，就会立即调用handleSuccess函数-->
            <el-upload
                :action="uploadURL"
                :on-preview="handlePreview"
                :on-remove="handleRemove"
                list-type="picture"
                :headers="headerObj" :on-success="handleSuccess">
              <el-button size="small" type="primary">点击上传</el-button>
            </el-upload>
          </el-tab-pane>
          <el-tab-pane label="商品内容" name="4">
            <!-- 富文本编辑器组件-->
            <quill-editor v-model="addForm.goods_introduce"></quill-editor>
            <!-- 添加商品的按钮-->
            <el-button type="primary" class="btnAdd" @click="add">添加商品</el-button>
          </el-tab-pane>
        </el-tabs>
      </el-form>
    </el-card>

    <!-- 图片预览框-->
    <el-dialog
        title="图片预览"
        :visible.sync="previewVisible"
        width="50%">
      <img :src="previewPath" class="previewImg" alt="">
    </el-dialog>
  </div>
</template>

<script>
import _ from 'lodash'

export default {
  name: "Add",
  data(){
    return {
      // 被激活的步骤条及tab
      activeIndex:'0',
      // 添加商品的表单数据对象
      addForm:{
        goods_name:'',
        goods_price:0,
        goods_weight:0,
        goods_number:0,
        // 商品所属的分类数组
        goods_cat: [],
        // 上传的图片
        pics:[],
        // 商品内容的详情描述
        goods_introduce:'',
        // 商品的参数（数组），包含 `动态参数` 和 `静态属性`
        attrs:[]
      },
      // 表单验证规则
      addFormRules:{
        goods_name: [{required: true, message: '请输入商品名称', trigger: 'blur'}],
        goods_price: [{required: true, message: '请输入商品价格', trigger: 'blur'}],
        goods_weight: [{required: true, message: '请输入商品重量', trigger: 'blur'}],
        goods_number: [{required: true, message: '请输入商品数量', trigger: 'blur'}],
        goods_cat: [{required: true, message: '请选择商品分类', trigger: 'blur'}],
      },
      // 商品分类列表
      catelist:[],
      // 级联选择器的配置项
      cateProps:{
        expandTrigger: 'hover',
        label: 'cat_name',
        value: 'cat_id',
        children: 'children',
      },
      // 动态参数列表数据
      manyTableData:[],
      // 静态属性列表数据
      onlyTableData:[],
      // 图片的上传URL
      uploadURL: 'http://127.0.0.1:8888/api/private/v1/upload',
      // 图片上传时的header请求头
      headerObj:{
        Authorization: window.sessionStorage.getItem('token')
      },
      // 预览图片地址
      previewPath: '',
      // 控制图片预览框的出现
      previewVisible: false,
    }
  },
  created() {
    this.getCateList()
  },
  methods:{
    // 获取商品所有的分类数据
    async getCateList(){
      const {data:res} = await this.$http.get('categories')
      if (res.meta.status !== 200){
        return this.$message.error('获取商品分类数据失败！')
      }
      this.catelist = res.data
      // console.log(this.catelist);
    },
    // 级联选择器变化的触发函数
    handleChange(){
      // console.log(this.addForm.goods_cat);
      if (this.addForm.goods_cat.length !== 3){
        this.addForm.goods_cat = []
      }

    },
    // 切换标签页触发的函数
    beforeTabLeave(activeName, oldActiveName){
      // return false会组织标签页的切换
      // 不可以直接在箭头函数中return false
      let flag = true
      this.$refs.addFormRef.validate(valid => {
        return flag = valid
      })
      if (!flag || (oldActiveName === '0' && this.addForm.goods_cat.length !== 3)) {
        this.$message.error('请填写选择所有必须项！')
        return false
      }
    },
    // 点击标签tab事件
    async tabClicked(){
      // 访问动态参数面板
      if (this.activeIndex === '1'){
        const {data:res} = await this.$http.get(`categories/${this.cateId}/attributes`,{
          params:{sel: 'many'}
        })
        if (res.meta.status !== 200){
          return this.$message.error('获取动态参数列表失败！')
        }
        res.data.forEach(item => {
          item.attr_vals = item.attr_vals.length === 0 ? [] : item.attr_vals.split(' ')
        })
        this.manyTableData = res.data
      }
      else if (this.activeIndex === '2'){
        const {data:res} = await this.$http.get(`categories/${this.cateId}/attributes`,{
          params:{sel: 'only'}
        })
        if (res.meta.status !== 200){
          return this.$message.error('获取商品属性列表失败！')
        }
        this.onlyTableData = res.data
      }
    },
    // 处理图片预览效果
    handlePreview(file){
      // console.log(file);
      this.previewPath = file.response.data.url
      this.previewVisible = true
    },
    // 处理移除图片的操作
    handleRemove(file){
      // 1. 获取将要删除的图片的临时路径
      // 2. 从pics数组中，找到这个图片对应的索引值(pic是属性，可参考handleSuccess函数中picInfo的定义)
      // 3. 调用数组的splice方法，把图片信息对象从pics数组中删除
      const filePath = file.response.data.tmp_path
      const i = this.addForm.pics.findIndex(x => x.pic === filePath)
      this.addForm.pics.splice(i,1)
      // console.log(this.addForm);
    },
    // 监听图片上传成功的事件
    handleSuccess(response){
      // console.log(response);
      // 1. 拼接得到一个图片信息对象
      const picInfo = {
        pic: response.data.tmp_path
      }
      // 2. 将图片信息对象push到pics数组中
      this.addForm.pics.push(picInfo)
      // console.log(this.addForm);
    },
    // 添加商品
    add(){
      this.$refs.addFormRef.validate(async valid => {
        // !valid为true，意味着valid为false，此时直接return
        if (!valid) {
          return this.$message.error('请填写必要的表单项！')
        }
        // 执行添加的业务逻辑
        // 使用Lodash做深拷贝
        const form = _.cloneDeep(this.addForm)
        form.goods_cat = form.goods_cat.join(',')
        // 处理动态参数
        this.manyTableData.forEach(item => {
          const newInfo = {
            attr_id: item.attr_id,
            attr_value: item.attr_vals.join(' ')
          }
          // console.log(newInfo);
          this.addForm.attrs.push(newInfo)
        })
        // 处理静态属性
        this.onlyTableData.forEach(item => {
          const newInfo = {
            attr_id: item.attr_id,
            attr_value: item.attr_vals
          }
          this.addForm.attrs.push(newInfo)
        })
        form.attrs = this.addForm.attrs
        // console.log(form);
        // 发起请求添加商品
        // 商品的名称必须唯一
        const {data:res} = await this.$http.post('goods',form)
        if (res.meta.status !== 201){
          this.$message.error('添加商品失败！')
        }
        this.$message.success('添加商品成功！')
        this.$router.push('/goods')
      })
    }
  },
  computed:{
    cateId(){
      if (this.addForm.goods_cat.length === 3){
        return this.addForm.goods_cat[2]
      }
      return null
    }
  }
}
</script>

<style lang="less" scoped>
.el-checkbox{
  margin: 0 10px 0 0 !important;
}
.previewImg{
  width: 100%;
}
.btnAdd{
  margin-top: 15px;
}
</style>